Nowr?z (lang-fa?????, IPA-fano???u?zIPA, "New Day", originally "New Light") is a traditional ancient Iranian (Iranian peoples) festival which celebrates the start of the Iranian (Iranian calendar) New Year. Nowruz is also widely referred to as the Persian New Year.

Nowruz is celebrated and observed by Iranian peoples and the related cultural continent (Greater Iran) and has spread in many other parts of the world, including parts of Central Asia, South Asia, Northwestern China (Xinjiang), the Crimea and some ethnic groups in Albania, Bosnia, Serbia and the Republic of Macedonia.

Nowruz marks the first day of spring and the beginning of the year in Iranian calendar. It is celebrated on the day of the astronomical vernal equinox, which usually occurs on March 21 or the previous/following day depending on where it is observed. As well as being a Zoroastrian holiday and having significance amongst the Zoroastrian ancestors of modern Iranians, the same time is celebrated in the Indian sub-continent as the new year. The moment the Sun crosses the celestial equator and equalizes night and day is calculated exactly every year and Iranian (Iranian people) families gather together to observe the rituals.

Originally being a Zoroastrian festival (Zoroastrian festivals), and the holiest of them all, Nowruz is believed to have been invented by Zoroaster himself, although there is no clear date of origin. Since the Achaemenid era (Achaemenid Empire) the official year has begun with the New Day when the Sun leaves the zodiac of Pisces and enters the zodiacal sign of Aries, signifying the Spring Equinox. The Jewish festival of Purim is probably adopted from the Persian New Year. It is also a holy day for Sufi (Sufism)s, Ismaili (Ismailism)s, Alawites, Alevis, and adherents of the Bah�� Faith.cite web url = title = The Bahai Calendar accessdate = 2007-03-19

The term Nowruz in writing, first appeared in Persian (History of Iran) records in the second century AD, but it was also an important day during the time of the Achaemenids (Achaemenid dynasty) (c. (circa) 648-330 BC), where kings from different nations under the Persian empire used to bring gifts to the Emperor, also called King of Kings (Shahanshah), of Persia on Nowruz.

The UNs General Assembly (United Nations General Assembly) in 2010 recognized the International Day of Nowruz, describing it a spring festival of Persian (Persian people) origin which has been celebrated for over 3,000 years. During the meeting of The Inter-governmental Committee for the Safeguarding of the Intangible Heritage of the United Nations, held between 28 September – 2 October 2009 in Abu Dhabi, Nowr?z was officially registered on the UNESCO List of the Intangible Cultural Heritage of Humanity.